Nonlinear photonic pre-processing bi-spectrum optical receivers for long haul optically amplified transmission systems

The high order spectrum (HOS) technique is proposed as a non linear (NL) signal processing technique for digital optical receiver system for long haul optically amplified fiber transmission systems. The optical receivers employing higher order spectral photonic pre-processor and VLSI electronic system for the electronic decoding and evaluation of the bit error rate of the transmission system. A photonic signal pre-processing system is developed to generate the triple correlation via the third harmonic conversion in a NL optical waveguide is employed as the photonic pre-processor to generate the essential part of a triple correlator. The performance of an optical receiver incorporating the HOS processor is given for long haul phase modulated fiber transmission.